PROJECT SUMMARY Antiretroviral therapy has transformed HIV into a chronic disease and, in countries like the US, most treated HIV+ individuals die from causes other than AIDS or opportunistic infections. Chronic conditions like end-stage liver disease (ESLD) are increasingly common and contribute significantly to morbidity and mortality in individuals living with HIV. Liver transplantation is a treatment option for individuals with ESLD, and the number of HIV+ candidates who receive liver transplants each year has increased more than 4-fold since 2002. However, little is known about ESLD patients with HIV on the national liver transplant waitlist in terms of mortality, allocation priority, and survival benefit. Given the organ shortage, the sickest liver transplant candidates receive priority for liver allocation. This allocation priority is based on a scoring system that may not adequately capture the disease severity of candidates with HIV. Despite their importance, these questions remain unanswered since the HIV status of waitlist candidates is not collected in the national transplant registry. To address this knowledge gap, we have created a novel data linkage to identify the HIV status of LT waitlist candidates. In an effort to understand the impact of HIV in ESLD, we have designed the proposed study, which aims to answer the following questions: 1. Are ESLD patients with HIV at an increased risk of death on the waitlist compared to similar candidates without HIV? 2. Do ESLD patients with HIV receive the appropriate allocation priority, based on their disease severity? 3. If ESLD patients with HIV undergo liver transplantation, does it improve their overall survival? The proposed study findings are critical to the development of robust, evidence-based guidelines for the management of ESLD patients with HIV. Understanding the specific risk factors for waitlist mortality, the impact of current liver transplant allocation methods, and the potential survival benefit of liver transplantation for ESLD patients with HIV can aid patient-centered clinical decision-making and, ultimately, improve outcomes in this vulnerable population. Importantly, if successful, this study will generate the data necessary to develop an allocation paradigm that better predicts disease severity for ESLD patients with HIV. This work will be immediately applicable as there is a growing number of ESLD patients with HIV on the waitlist and receiving liver transplants, given the changing HIV landscape and recent policy changes for HIV+ organ donation.